Field of the Invention
The invention generally relates to task assignment in a multi-core processor system, and more particularly, to task assignment that cross refers to task assignment information corresponding to multiple scheduling classes at the same time.
Description of the Related Art
In electronic devices such as smartphones, notebooks, and tablet computers, a task scheduler is configured to schedule or assign tasks a multi-core processor system including a plurality of processor cores. The tasks can be scheduled according to different scheduling algorithms, which for example, can include RT (real-time) scheduler, and/or a Completely Fair Scheduler (CFS), and/or any specific scheduling algorithm. Tasks can be referred to according to their corresponding scheduling algorithms. For example, tasks scheduled according to RT scheduler can be referred to as RT tasks, and tasks scheduled according to CFS can be referred to as CFS tasks.
When the task scheduler assigns tasks to the processor cores, it refers to task assignment information about tasks currently assigned to the processor cores. In addition, the task scheduler assigns RT tasks and CFS tasks independently. Specifically, when the task scheduler assigns a RT task, it refers to only task assignment information about RT tasks currently assigned to the processor cores, without considering CFS tasks or any other tasks different from RT tasks currently assigned to the processor cores. Similarly, when the task scheduler assigns a CFS task, it does not refer to task assignment information about tasks other than CFS tasks assigned to the processor cores. In summary, when the task scheduler assigns a task scheduled by a specific scheduling algorithm, it does not consider tasks scheduled by any other scheduling algorithms different from the specific scheduling algorithm.
However, load imbalance often occurs and the performance of the processor cores is not optimal. Solving the problems to improve task assignment and system performance in a multi-core processor system is therefore a subject worthy of discussion.